In order to store large quantities of data, the data are recorded on data carriers, e.g. on magnetic tape cartridges, magnetic discs or optical plates (CD, DVD). In order to store a large number of such data carriers and to be able to access them, devices are used which are known under the designation ‘library’ or ‘autoloader’. A large number of data carriers are disposed in corresponding receptacles in these devices and can be removed from and inserted into the respective receptacles by means of a robot unit. In this way, the data carriers can be selectively released or transferred to a drive arranged in the device or inversely reinserted into a selected receptacle.
In such devices, which can accommodate a large number of data carriers, it is known to arrange the receptacles for several data carriers in a common magazine, which can be removed from the housing of the device. Data carriers, to which a current access is not necessary, can thus be archived in an orderly manner in the magazines. Likewise, it is thus possible to exchange a large number of data carriers disposed in a magazine jointly and to equip the magazines outside the device with the data carriers thereby simplifying and reducing the time required for changing the data carriers available for access in the device.
A device for storing data carriers of the type mentioned at the onset is known from U.S. Pat. No. 6,353,581 B1. In this device, the last receptacle of at least one magazine is designed as a change receptacle. This change receptacle is accessible from the outer side of the housing of the device so that a data carrier can be removed from or inserted into this change receptacle without having to remove the entire magazine from the housing. The resulting advantage is that a single data carrier can be exchanged without having to interrupt the operation of the device since the remaining receptacles of the magazine remain in their operating position and are accessible to the robot unit. The change receptacle thus serves as the mailbox, using which individual data carriers can be removed from or inserted into the device during the operation of the latter, the robot unit carrying out the internal transport of the data carriers between the change receptacle and the remaining receptacles.
In the device known from U.S. Pat. No. 6,353,581 B1, the data carriers, namely magnetic tape cartridges, are arranged in the receptacles of the magazine edgewise side by side, i.e. with their flat sides adjoining to one another. The change receptacle is located such that its flat side adjoins to the vertical panel of the housing of the device. The change receptacle can swivel about an axis that is parallel to the vertical front panel of the housing so that the receptacle can be extended from the front side of the housing in order to exchange the data carrier in the change receptacle. The edgewise vertical arrangement of the data carriers, particularly of magnetic tape cartridges, in the magazines requires a relatively large minimum installation height of the device. The space taken up by the device frequently plays an essential role in the case of a smaller and average data storage requirement. Since the device is inserted into a standardized rack in most applications, the installation height is the essential criterion for the space utilized.